Spectroscopy is a family of techniques, as opposed to being one technique. All spectroscopy techniques, whether based on absorption, optical density, scattering, fluorescence emission, fluorescence anisotropy, Raman spectroscopy, or others, involve emission of light from a light source. Emission of light is often accompanied by heating, which may cause problems in signal to noise ratio, emission intensity or other aspects of measurement accuracy, and may also cause problems. Heating also may result in degradation of the light source. A variety of approaches have been taken to mitigating the effect of heating on output from a light source, often by providing airflow for cooling fans.
Different types of spectroscopy may often be used in combination to greater advantage than one type of spectroscopy alone. A system with more than one light source may require greater cooling capacity than a system with only one light source. Similarly, systems with smaller profiles may suffer from effects of heating to a greater degree than system with larger footprints and more accommodation in the system for cooling by airflow or other methods.